High current disconnecting switch



y 1965 A. LATOUR 3,196,240

HIGH CURRENT DISCONNECTING SWITCH Filed Dec. 15, 1961 United States Patent 3,1?6,249 HEGH CURRENT BESCGNNEtITlNG SWITCH Andre Latent, Grenoble, France, assigner to Etablissemeats Merlin & Gerin 8A., Grenoble, France Filed Dec. 15, 1961, Ser'. No. 159,612 (Ilaims priority, application France, Dec. 20, 1.960, 4,317

tllairns. (Si. 200-171) This invention relates generally to contact assemblies for electric switches having a switch blade and more especially to such switches designed for high current-carrying capacity.

Switches of this kind are known in which a single disconnecting point per pole is provided, the disconnecting point being, by definition, a point Where the circuit is opened and closed without the formation of an arc. The switch blade is therefore only used to carry the current and not for breaking and making the current, this generally being effected by arcing contacts.

It is an object of the present invention to provide an improved contact assembly in which in the closed position of the switch a compensation is provided for the electrodynaniic forces which tend to open the blade at the occurrence of high current intensities.

These and other objects and advantages will be apparent from the following specification, taken in conjunction with the accompanying drawing, of an embodiment of the invention given merely for the purpose of illustration.

In this drawing which illustrates diagrammatically a side elevation of a contact assembly according to the invention, 11 designates the blade which is pivotally mounted on the stationary axis 12 supported by two side plates of which only the back plate 13 is shown. This blade which is shown in the open position by solid lines and in the closed position by dotted lines, may be operated by any appropriate means not shown. The current is transmitted to the blade by a series of conductive means consisting of elongated linear juxtaposed fingers having substantially parallel longitudinal axes which are perpendicular to the direction of the blade in the closed position of the switch and forming jaws 14 between which engages the end 17 of the blade while the other end 13 can move into and out of engagement with jaws constituted the same as jaws 14. The current passes from the jaws l4 and 15 into the switch blade 11 by means of stationary contact members constituted by raised portions 19 respectively 20 of the jaw contact fingers 14 and 15. The pivot axis 12 is disposed between the jaw contacts 4 and 15 and advantageously nearer to the jaw contacts 14 so as to secure a large stroke to the end 18 of the blade.

it is to be noted that, in the closed position of the switch, the current paths coming from the jaw contacts 14 form bends (see the arrows) and create repulsive forces which tend to turn the blade 11 in counter-clockwise direction and so compensate the opposed repulsive force produced at the other end 18 of the blade which tends to swing the blade in the clockwise direction. The end of the blade has been provided, in a known manner,

Patented July 2%, 19555 ice with saw-cuts 36, to direct the flow path of the current tower the right side or" the blade. The repulsion eflect at the end of the blade is reduced, thus decreasing substantially the force necessary to maintain the blade in the closed position when a short-circuit or a current of very high intensity appears.

The arrangement described has moreover the advan tage of supplanting the flexible conductors used until now which, in the case of very high current intensities, may cause disturbances.

What is claimed is:

l. A high current disconnecting switch comprising in combination:

(a) a pair of stationary elongated spring blade contacts (b) an elongated blade pivoted to bridge said contacts in the closed position of said switch (0) said contacts and said blade being disposed to provide a pair of contact surfaces located respectively adjacent the extremities of said blade (d) said blade being pivoted between said contact surfaces for the switch opening and closing movement,

(e) said contacts being disposed respectively in the immediate neighborhood of said surfaces substantially parallel to each other and generally perpendicular to the length of said elongated blade in the closed position of the switch to produce current flows in said contacts in opposite directions, and

(f) said elongated blade having slots at least in the immediate vicinity of one of said contact surfaces generally parallel to the direction of said elongated spring contacts.

2. A switch as in claim 1 and wherein (a) said elongated blade when in closed position has the width portion extending outwardly from and beyond the extremities of said elongated spring contacts.

3. A switch as in claim 2 and wherein (a) said pivot lies in the area which falls between said pair of stationary elongated spring contacts, and

(b) said blade extending portion lies outside said area between said pair of stationary elongated spring contacts.

d. A switch as in claim 1 and wherein (a) said blade is angled outwardly.

5. A switch as in claim 4 and wherein (a) said pivot is positioned substantially at the vertex of said angle.

References Cited by the Examiner UNITED STATES PATENTS 1,546,272 7/25 Wedeman 200-466 2,120,396 6/38 Domaleski 200-166 2,390,585 12/45 Hartley 200-162 2,765,380 10/56 raybill 200-470 2,779,830 1/57 Turner et al. 20048 ROBERT K. SCHAEFER, Primary Examiner.

BERNARD A. GILHEANY, Examiner. 

1. A HIGH CURRENT DISCONNECTING SWITCH COMPRISING IN COMBINATION: (A) A PAIR OF STATIONARY ELONGATED SPRING BLADE CONTACTS (B) AN ELONGATED BLADE PIVOTED TO BRIDGE SAID CONTACTS IN THE CLOSED POSITION OF SAID SWITCH (C) SAID CONTACTS AND SAID BLADE BEING DISPOSED TO PROVIDE A PAIR OF CONTACT SURFACES LOCATED RESPECTIVELY ADJACENT THE EXTREMITIES OF SAID BLADE (D) SAID BLADE BEING PIVOTED BETWEEN SAIN CONTACT SURFACES FOR THE SWITCH OPENING AND CLOSING MOVEMENT, (E) SAID CONTACTS BEING DISPOSED RESPECTIVELY IN THE IMMEDIATE NEIGHBORHOOD OF SAID SURFACES SUBSTANTIALLY PARALLEL TO EACH OTHER AND GENERALLY PERPENDICULAR TO THE LENGTH OF SAID ELONGATED BLADE IN THE CLOSED POSITION OF THE SWITCH TO PRODUCE CURRENT FLOWS IN SAID CONTACTS IN OPPOSITE DIRECTIONS, AND (F) SAID ELONGATED BLADE HAVING SLOTS AT LEAST IN THE IMMEDIATE VICINITY OF ONE OF SAID CONTACT SURFACES GENERALLY PARALLEL TO THE DIRECTION OF SAID ELONGATED SPRING CONTACTS. 